Alkalistable endo-β-1,4-xylanase production from a newly isolated alkalitolerant Penicillium sp. SS1 using agro-residues

Abstract

Thermostable and alkalitolerant xylanases have got intense research focus due to their vast applications in various industries including pulp and paper, food, feed, textile, biofuel, etc. In the present investigation, a Penicillum sp. SS1 isolated from degrading woody material was found to produce moderately thermoactive and alkalistable endo-β-1,4-xylanase (xylanase). Maximum xylanase production was observed after fourth day of fermentation (43.84 IU/ml). The organism produced substantial quantities of xylanase using agricultural residues like wheat bran (20.6 IU/ml), rice bran (21.8 IU/ml) and sawdust (10.7 IU/ml) as carbon sources. The enzyme preparation was totally free of filter paper activity (FPase) and possessed negligible carboxymethyl cellulase (CMCase) activity; this could be an important feature of enzyme if the intended application of enzyme is in pulp and paper industries. Among nitrogen sources examined, yeast extract supported maximum xylanase production (45.74 IU/ml), and was followed by soybean meal (22.2 IU/ml) and ammonium sulphate (20 IU/ml). Maximum xylanase production was observed at initial medium pH 9 (25.6 IU/ml); however, at pH 8 and 10 also significantly high enzyme titre was observed (24 and 21.2 IU/ml, respectively). Thus, Penicillium sp. SS1 displayed capability of growing and producing xylanase at high alkaline pH (8–10). Maximum xylanase activity was reported at 50 °C, however, significantly high activity was observed at 60 °C (65.4%), however, at 70–80 °C activity was lost considerably. At 50–60 °C the enzyme retained very high activity up to 30–60 min (91–100%), however, prolonged incubation (90 min) caused considerable activity reduction (residual activity 63–68%).

Optimization of Laccase Production by Locally Isolated Trichoderma muroiana IS1037 Using Rubber Wood Dust as Substrate

“…Rubberwood dust is abundantly available in Malaysia, and this substrate could be used as a carbon source for laccase production. Moreover, lignocellulosic waste utilization could play a vital role in solving environmental waste disposal problems (Bajaj et al 2011). Table 3 illustrates laccase production by different species of fungi grown using different types of substrates.…”

A Highly Thermostable Xylanase fromStenotrophomonas maltophilia: Purification and Partial Characterization

“…Most of the xylanases characterized so far showed optimum activity at acidic, neutral, or slightly alkaline pH (7.0-8.0) and at temperatures between 40°C and 60°C. Also, despite extensive exploitation of microbial diversity for novel xylanase producers, however, xylanases that are thermostable and alkali tolerant are limited [ 2 , 8 ]. In the present study, xylanolytic Stenotrophomonas maltophilia was isolated from saw-dust dump and cultural conditions were studied for maximum xylanase production.…”

Xylan deterioration approach: Purification and catalytic behavior optimization of a novel β-1,4-d-xylanohydrolase from Geobacillus stearothermophilus KIBGE-IB29

“…Penicillium sp. endo-xylanase lost up to 63 to 68% activity at 60 °C after 90 min [ 37 ]. Thermal stability of enzyme encompasses kinetic stability, thermodynamics and highly dependent on the molecular interactions including disulfide bond, hydrogen bond, binding of metals as well as hydrophobic and electrostatic interactions present within the structure of an enzyme.…”